Results 151 to 160 of about 107,717 (203)
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Phase-shifting speckle interferometry
Applied Optics, 1985Speckle patterns have high frequency phase data, which make it difficult to find the absolute phase of a single speckle pattern; however, the phase of the difference between two correlated speckle patterns can be determined. This is done by applying phase-shifting techniques to speckle interferometry, which will quantitatively determine the phase of ...
Katherine Creath
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Speckle interferometry in transparent media
Applied Optics, 1986Speckle interferometry is applied to transparent media to obtain measurements of full-field density variations. Speckle interferometry can present decreased vibration sensitivity compared to some wave front comparison methods while maintaining high sensitivity.
D D, Verhoeven, P V, Farrell
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Speckle photography combined with speckle interferometry
Optics and Lasers in Engineering, 2004By combining speckle interferometry (SI) measurements with speckle photography, the fringe visibility can be kept high despite the presence of a large bulk or rotating motion of the object. This combined technique improves the usability and measuring range of both pulsed and phase-stepped SI-methods. This paper reviews the theory of fringe formation in
M Sjödahl
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Subfeature speckle interferometry
Optics Letters, 1995A novel speckle technique, subfeature speckle interferometry, is introduced that relies on the amplitude interference of two independent speckle patterns, originating from coherent illumination, by use of an optical system that produces interferometric quality interference fringes on a scale comparable with the speckle correlation length.
D, Burckel +4 more
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Hololens in speckle and speckle shear interferometry
Applied Optics, 1985This paper presents a number of methods to obtain in-plane displacement, out of plane displacement and slope data using holographic optical elements. The results obtained with a hololens and a holoshear lens are as good as those obtained with conventional optical systems.
C, Joenathan, R K, Mohanty, R S, Sirohi
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Stellar speckle interferometry
Physics Bulletin, 1975Stellar speckle interferometry is a technique for obtaining diffraction-limited resolution of stellar objects despite the presence of the turbulent atmosphere which limits the resolution of conventional long-exposure pictures to approximately one arc second.
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Spectral Speckle Interferometry
Astrophysics and Space Science, 1989A method of obtaining an objective prism spectrum of a stellar object with diffraction-limited spatial resolution is described.
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Materials Testing, 1996
With the electronic laser speckle interferometry (ESPI) it is possible to make deformation and strain fields visible. An easy to use sensor is presented. For demonstration the inhomogeneous deformation behaviour of laser-welded aluminium sheet is shown. At lower load the deformation is homogeneous, at higher load there is a deformation concentration in
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With the electronic laser speckle interferometry (ESPI) it is possible to make deformation and strain fields visible. An easy to use sensor is presented. For demonstration the inhomogeneous deformation behaviour of laser-welded aluminium sheet is shown. At lower load the deformation is homogeneous, at higher load there is a deformation concentration in
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Characterization of bones by speckle interferometry
Journal of Medical Engineering & Technology, 2003Speckle photography interferometry (SPI) is used to evaluate the stress-strain behaviour of animal bones under loads by recording the speckle fields generated on the bone surface and thus finding the relationship between the fractal dimension D(s) and the compression load P. The procedure consists of application of slow and monotonous compression loads,
J, Horta +3 more
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SPIE Proceedings, 1985
The atmosphere of the earth restricts the resolution of conventional astrophotography to about 1". We will discuss various high-resolution speckle methods which can overcome image degradation caused by the atmosphere and telescope aberrations. All methods yield diffraction-limited resolution, for example 0.03" for a 3.6m telescope. We will show various
G. Weigelt +5 more
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The atmosphere of the earth restricts the resolution of conventional astrophotography to about 1". We will discuss various high-resolution speckle methods which can overcome image degradation caused by the atmosphere and telescope aberrations. All methods yield diffraction-limited resolution, for example 0.03" for a 3.6m telescope. We will show various
G. Weigelt +5 more
openaire +1 more source